MDNews - San Antonio

ALTHOUGH IT IS ESTABLISHED THAT THE INCIDENCE OF EPILEPSY IS HIGHER AMONG INDIVIDUALS WITH AUTOIMMUNE DISORDERS — PARTICUL ARLY THOSE THAT DIRECTLY AFFECT THE BR AIN — A DANISH STUDY PUBLISHED IN NEUROLOGY HA S SPECIFICALLY LINKED EPILEPSY RISK AMONG CHILDREN TO WHE THER THEIR MOTHERS HAVE RHEUMATOID ARTHRITIS (R A). E ARLIER RE SE ARCH, INCLUDING a 2014 study by scientists at Boston Children's Hospital, has linked epilepsy and autoimmune disorders. That prompted Ane Lilleøre Rom, PhD, of the Department of Obstetrics and Research Unit Women's and Children's Health, the Juliane Marie Centre, Copenhagen University Hospital, Rigshospitalet, and colleagues to explore the topic further. They classifi ed some 2 million Danish children born between Jan. 1, 1977, and Dec. 31, 2008, based on whether they were exposed to maternal or paternal R A, or not exposed to R A at all. They then tracked the incidence of epilepsy among the children for an average of 16 years. Children exposed to maternal RA had an overall 26 percent higher risk of early- and late-childhood epilepsy than those who were not exposed, whereas paternal R A had no eff ect. Further, children whose mothers had clinical R A, meaning they had the condition at the time they gave birth, had a higher risk of early-childhood epilepsy than those whose mothers had preclinical R A, or R A that was diagnosed after childbirth. Rom cautions that the total number of aff ected children is comparatively small and says the study's key benefi t is that it provides a tool for better understanding some of the mechanisms behind epilepsy. "Though children exposed to maternal clinical R A were up to 90 percent more likely [than children who were not exposed] to develop epilepsy, ... this in absolute numbers translates to 3 percent of the children," she explains. "Thus, 97 percent of the children born to mothers with clinical R A will not develop epilepsy." RESEARCH IMPLICATIONS Rom is looking into whether other maternal autoimmune diseases increase the risk of epilepsy in children. Her research suggests additional avenues of investigation as well. "The fact that paterna l R A did not inf luence the risk of childhood epilepsy makes it more likely that there is a fetal environmental exposure resulting in an increased risk of epilepsy, rather than a heritable factor," Russell C. Dale, MRCP, PhD, and J. Nicholas Brenton, MD, write in an editorial accompanying the Neurology study. "While therapies to treat maternal R A could conceivably be an alternative exposure factor that increases epilepsy risk, the fact that mothers with preclinical R A ... had off spring with an increased risk of epilepsy makes this less plausible." n Incidence Gap Approximately 1.5 million Americans have rheumatoid arthritis. The incidence of the disease is almost three times greater among women than among men, according to the Arthritis Foundation. Maternal Rheumatoid Arthritis STUDY FINDS Raises Childhood Epilepsy Risk BY HANNAH STUART 1 8

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